Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, São Paulo, Brazil; Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA; Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA.
Mol Phylogenet Evol. 2018 Oct;127:800-812. doi: 10.1016/j.ympev.2018.06.027. Epub 2018 Jun 20.
Curimatidae, the fourth largest family of detritivorous Neotropical characiform fishes, encompasses eight extant genera and over 110 species dwelling in diverse freshwater habitats from Costa Rica to Argentina. Extensive phylogenetic analyses of soft anatomy and osteology provided evidence for intergeneric and most interspecific relationships, and formed the basis of curimatid taxonomy for nearly 40 years. However, that morphological phylogeny demonstrated incomplete phylogenetic resolution at various scales and has never been tested with extensive molecular data. Herein, we infer molecular phylogenies spanning ∼70% of the known species diversity using three nuclear and three mitochondrial loci. Topologies from concatenated likelihood and Bayesian analyses and coalescent Bayesian species trees agree broadly with each other, and with the prior morphological hypothesis in many, but not all respects. All molecular analyses support the monophyly of Curimatidae and of six of its constituent genera, and agree on the placement of Curimatopsis as sister to all other curimatids. DNA-based intergeneric relationships differ substantially from prior morphological hypotheses by placing Curimata sister to Potamorhina and Psectrogaster sister to Pseudocurimata, rather than in a ladderized arrangement. Our results also resolve a major uncertainty in the morphological tree by revealing Cyphocharax, a genus for which no anatomical synapomorphy has ever been proposed, as a paraphyletic assemblage containing a monophyletic Steindachnerina and a polyphyletic Curimatella. Overall, the phylogeny expands substantially our understanding of the morphology, phylogenetics and evolution of the Curimatidae, and will guide future intrageneric studies by improving precision in the choice of comparative taxa.
锯脂鲤科是新热带碎屑性脂鲤目鱼类中第四大科，包含 8 个现存属和 110 多种鱼类，栖息在从哥斯达黎加到阿根廷的各种淡水生境中。对软组织和骨骼的广泛系统发育分析提供了属间和大多数种间关系的证据，并为近 40 年来的锯脂鲤科分类学奠定了基础。然而，该形态系统发育在不同尺度上显示出不完全的系统发育分辨率，并且从未使用广泛的分子数据进行过测试。在此，我们使用 3 个核和 3 个线粒体基因座推断出涵盖已知物种多样性约 70%的分子系统发育。串联似然和贝叶斯分析以及合并贝叶斯种树的拓扑结构彼此之间以及与之前的形态假说在许多方面都基本一致，但并非所有方面都一致。所有分子分析都支持锯脂鲤科及其 6 个组成属的单系性，并支持 Curimatopsis 作为所有其他锯脂鲤科鱼类姐妹群的位置。基于 DNA 的属间关系与之前的形态假说有很大的不同，将 Curimata 置于 Potamorhina 姐妹群中，而将 Psectrogaster 置于 Pseudocurimata 姐妹群中，而不是呈梯级排列。我们的结果还通过揭示 Cyphocharax 是一个没有任何解剖学同源特征的属，而是一个包含单系 Steindachnerina 和多系 Curimatella 的并系集合，解决了形态树上的一个主要不确定性。总的来说，该系统发育大大扩展了我们对锯脂鲤科形态、系统发育和进化的理解，并将通过提高比较分类群选择的精度来指导未来的属内研究。
